Most people familiar with SCUBA diving have heard horror stories at one time or another about decompression sickness (DCS). Commonly referred to as the bends or caisson disease, decompression sickness is what happens to divers when nitrogen bubbles build up in the body and are not properly dissolved before resurfacing. As a diver descends further into the depths, pressure increases around the diver’s body, and nitrogen is then absorbed into the diver’s body tissue. This in itself is not exactly harmful, as nitrogen can be safely absorbed to a certain extent.
However, nitrogen absorption does become an issue when that pressure is released. In order for nitrogen to be released from the diver’s body at an acceptable rate, decompression stops must be performed when certain depths or dive times are involved. Also known as off-gassing, decompression stops allow nitrogen to slowly escape from the body’s tissues and revert into small, harmless gas bubbles. When off-gassing occurs too rapidly, the diver may then experience decompression sickness. General symptoms include fatigue, red rash all over the body, numbness, upset stomach, vertigo, blurred vision, or pain.
There are several specific types of decompression sickness, but their severity can be narrowed down into two major types. Type I decompression sickness is the least serious and is not life threatening. It typically involves pain around the limbs and the joints due to nitrogen bubbles intensifying in the areas around the bone marrow or tendons, but can also manifest in the skin and lymphatic system. Itching, swelling, mottled skin, fatigue, and the feeling of skin “crawling” can all be symptoms of Type I DCS.
Type II DCS comprises the most serious forms of decompression sickness. Divers suffering this type can face tremendous complications. When nitrogen bubbles enter the nervous system, the entire body can be affected, at times one area more than others. If the present symptoms go untreated, paralysis or even death are possible. The following manifestations of Type II DCS are considered the most extreme:
Pulmonary DCS occurs when nitrogen bubbles form in the capillaries of the lungs, leading to both respiratory issues and heart problems. Burning chest pain, dry cough, and shortness of breath are all characteristics of pulmonary DCS.
- Neurological DCS occurs when nitrogen bubbles travel through the bloodstream, making their way into the brain. This can create blurred vision, headaches, and loss of consciousness, memory loss, unexplained mood swings, paralysis, numbness, and incontinence.
Because of the seriousness of DCS, divers are urged to create and stick to a dive plan to minimize any risk. But even the best laid plan may contain a simple error, or the diver may have a health complication they were previously unaware of, so anyone experiencing any of these symptoms should immediately seek medical attention.
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